Phosphorus-containing compositions, lubricants containing them and metal workpieces coated with same

ABSTRACT

Phosphorous acid diesters may be prepared by the reaction of an alkoxylated alkyl phenol with a phosphorus trihalide, or, in combination with water, with a triaryl phosphite. The former reaction also produces, as a byproduct, the corresponding halide. The resulting phosphorus-containing compositions are useful as additives for metal working lubricants.

This application is a continuation-in-part of copending application Ser.No. 36,113, filed May 4, 1979, now abandoned.

This invention relates to new compositions of matter, lubricatingcompositions containing them, a method of using such lubricatingcompositions in metal working operations, and metal workpieces coatedwith such lubricating compositions. In its broadest sense, the inventionis directed to phosphorus-containing compositions comprising at leastone compound having the formula

    [R.sup.1 --Ar.sup.1 (OR.sup.2).sub.x O].sub.2 POH

wherein:

Each R¹ is independently an aliphatic hydrocarbon-based radical havingfrom about 4 to about 100 carbon atoms;

each R² is independently an ethylene, trimethylene, loweralkyl-substituted ethylene or lower alkyl-substituted trimethyleneradical;

each Ar¹ is independently an aromatic radical; and

each x is independently an integer from 1 to 15.

As used herein, the term "aliphatic hydrocarbon-based radical" denotesan aliphatic radical having a carbon atom directly attached to theremainder of the molecule and having predominantly hydrocarbon characterwithin the context of this invention. Such radicals include thefollowing:

(1) Hydrocarbon radicals; that is, aliphatic (e.g., alkyl or alkenyl)and aromatic-substituted aliphatic radicals, and the like. Such radicalsare known to those skilled in the art; examples include butyl, octyl,decyl, dodecyl, eicosyl and triacontyl radicals (all isomers beingincluded).

(2) Substituted hydrocarbon radicals; that is, radicals containingnon-hydrocarbon substituents which, in the context of this invention, donot alter the predominantly hydrocarbon character of the radical. Thoseskilled in the art will be aware of suitable substituents (e.g., nitro,hydroxy, alkoxy, carbalkoxy).

(3) Hetero radicals; that is, radicals which, while predominantlyhydrocarbon in character within the context of this invention, containatoms other than carbon present in a chain or ring otherwise composed ofcarbon atoms. Suitable hetero atoms will be apparent to those skilled inthe art and include, for example, nitrogen, oxygen and sulfur.

In general, no more than about three substituents or hetero atoms, andpreferably no more than one, will be present for each 10 carbon atoms inthe hydrocarbon-based radical.

Preferably, the hydrocarbon-based radicals present as R¹ in thecompounds of this invention are free from acetylenic and usually alsofrom ethylenic unsaturation and have from about 4 to about 50 carbonatoms, desirably from about 6 to about 25 carbon atoms. The radicals areusually hydrocarbon.

The aromatic radical Ar¹ may be a single-ring, linked-ring or fused-ringcarbocyclic radical such as one derived from benzene, naphthalene,anthracene, phenanthrene, indene, byphenyl or the like, a similarradical containing substituents such as halo (especially chloro andbromo), nitro, hydroxy, carbalkoxy, sulfonic acid ester or the like, ora heterocyclic radical such as one derived from pyrrole, pyridine,indole or quinoline. Most often, however, Ar¹ is a single-ringcarbocyclic aromatic radical and especially a hydrocarbon radical (thatis, phenylene).

The radical R² is a divalent aliphatic radical having a straight chainof 2 or 3 carbon atoms. It is most often an ethylene or propyleneradical, but may also be ethylene containing a lower alkyl substituentother than methyl, or a trimethylene or lower alkyl-substitutedtrimethylene radical (the term "lower" referring to radicals containingno more than 7 carbon atoms).

As is apparent from the formula, the compounds present in thephosphorus-containing composition may contain the same or differentorganic groups attached through oxygen to phosphorus, provided that eachsuch group contains one or more alkoxy groups connecting the aromaticradical with the oxygen bonded to phosphorus. The integer x is usually 4or less, but it may be higher, especially when balanced by an R¹ radicallong enough to provide oil solubility.

It will be apparent that the phosphorus compounds in the compositions ofthis invention are diesters of phosphorous acid in which the alcoholmoieties are derived from certain oxyalkylated alkyl phenols and thelike. Many of these oxyalkylated alkyl phenols are sold by Rohm & HaasCompany under the designations "Triton X-15," "Triton X-35," etc. Forthe most part, R¹ in these "Triton" materials is an octyl radical,typically one derived from diisobutene.

The phosphorus-containing compositions of this invention may be preparedby a number of methods. One such method is by the reaction of at leastone triaryl phosphite, preferably triphenyl phosphite, with water and atleast one corresponding alcohol such as octylphenoxyethanol, the triarylphosphite, alcohol and water being present in approximately 3:2:1 molarratios. This reaction takes place under typical transesterificationconditions and the product contains a substantial proportion of thephosphorous acid diester.

A second and preferred method for preparing the compositions of thisinvention is by the reaction of at least one corresponding alcohol withat least one phosphorus trihalide of the formula PZ₃ wherein Z ischlorine or bromine, preferably chlorine. This reaction is typicallyeffected at temperatures between about 30° and about 150° C., by merelyheating the alcohol with the phosphorus trihalide. Hydrogen halide isevolved during the reaction and may be removed by absorption in analkaline material. If desired, the reaction may be carried out in thepresence of a substantially inert, normally liquid organic diluent,although no such diluent is ordinarily required.

If the mole ratio of alcohol to phosphorus halide is approximately 3:1,the products of the reaction are one mole of the phosphorous aciddiester and one mole of the corresponding halide. In a broad sense,therefore, the invention includes compositions comprising the previouslydefined phosphorus compound in combination with at least one halide ofthe formula

    R.sup.3 --Ar.sup.2 (OR.sup.4).sub.y Z

wherein R³ is an aliphatic hydrocarbon-based radical having from about 4to about 100 carbon atoms; R⁴ is an ethylene, trimethylene, loweralkyl-substituted ethylene or lower alkyl-substituted trimethyleneradical; Ar² is an aromatic radical; and y is an integer from 1 to 15.Under normal circumstances, as when the composition is prepared by thereaction of three moles of the alcohol with one mole of the phosphorustrihalide, R³ will be identical with R¹, R⁴ with R², Ar² with Ar¹ and ywith x. When the mole ratio varies substantially from 3:1 (for example,when it is as high as 5:1 or as low as 1.5:1), the resulting compositionmay comprise more than an equimolar amount of the halide with respect tothe phosphorus compound, or a mixture of the two compounds with excessalcohol, or a mixture of the phosphorous acid diester with monoestersand the like. Such mixtures are also within the scope of the invention,although compositions comprising a substantially equimolar amount of thephosphorous acid diester and halide are preferred.

When an alcohol comprising a single molecular species is employed ineither of the above-described reactions, the resulting phosphoruscompound has two identical organic groups attached through oxygen tophosphorus. When a mixture of alcohols is employed, it will be apparentthat the product may contain compounds in which the two organic groupsare different.

The preparation of the compositions of this invention is illustrated bythe following example. All parts are by weight.

EXAMPLE 1

A reaction vessel is fitted with a stirrer, condenser, addition funneland temperature indicating means; the open end of the condenser isattached to a vessel containing aqueous sodium hydroxide solution. Thereaction vessel is charged with 2055 parts (8.23 moles) of "TritonX-15," an octylphenoxyethanol. Phosphorus trichloride, 376 parts (2.74moles), is charged to the addition funnel and added slowly withstirring, starting at a temperature of about 24° C. The temperaturerises during the addition to about 59° C., whereupon the system ispurged with nitrogen and heated slowly to 120° C. as phosphorustrichloride addition continues. When addition is complete, heating at120° C. is continued for 15 minutes after which the mixture is vacuumstripped at 120° C. The product is the desired phosphite-chloridemixture containing 3.66% phosphorus and 4.31% chlorine, and having anacid number (bromphenol blue indicator) of 5.0.

The phosphorus-containing compositions of this invention are useful asadditives for lubricants, in which they function primarily to improvethe rust inhibiting and extreme pressure properties thereof. They can beemployed in a variety of lubricants based on diverse oils of lubricatingviscosity, including natural and synthetic lubricating oils and mixturesthereof. They are most useful in lubricants for metal working operationssuch as rolling, forging, hot-pressing, blanking, bending, stamping,drawing, cutting, punching, spinning and the like, and especially indrawing.

Natural oils include animal oils and vegetable oils (e.g., castor oil,lard oil) as well as liquid petroleum oils and solvent-treated oracid-treated mineral lubricating oils of the paraffinic, naphthenic ormixed paraffinic-naphthenic types. Oils of lubricating viscosity derivedfrom coal or shale are also useful base oils. Synthetic lubricating oilsinclude hydrocarbon oils and halo-substituted hydrocarbon oils such aspolymerized and interpolymerized olefins [e.g., polybutylenes,polypropylenes, propylene-isobutylene copolymers, chlorinatedpolybutylenes, poly(1-hexenes), poly(1-octenes), poly(1-decenes), etc.and mixtures thereof]; alkylbenzenes [e.g., dodecylbenzenes,tetradecylbenzenes, dinonylbenzenes, di-(2-ethylhexyl)benzenes, etc.];polyphenyls (e.g., biphenyls, terphenyls, alkylated polyphenyls, etc.),alkylated diphenyl ethers and alkylated diphenyl sulfides and thederivatives, analogs and homologs thereof and the like.

Alkylene oxide polymers and interpolymers and derivatives thereof wherethe terminal hydroxyl groups have been modified by esterification,etherification, etc. constitute another class of known syntheticlubricating oils. These are exemplified by the oils prepared throughpolymerization of ethylene oxide or propylene oxide, the alkyl and arylethers of these polyoxyalkylene polymers (e.g., methyl-polyisopropyleneglycol ether having an average molecular weight of 1000, diphenyl etherof polyethylene glycol having a molecular weight of 500-1000, diethylether of polypropylene glycol having a molecular weight of 1000-1500,etc.) or mono- and polycarboxylic esters thereof, for example, theacetic acid esters, mixed C₃ -C₈ fatty acid esters, or the C₁₃ Oxo aciddiester of tetraethylene glycol.

Another suitable class of synthetic lubricating oils comprises theesters of dicarboxylic acids (e.g., phthalic acid, succinic acid, alkylsuccinic acids and alkenyl succinic acids, maleic acid, azelaic acid,suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic aciddimer, malonic acid, alkyl malonic acids, alkenyl malonic acids, etc.)with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecylalcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycolmonoethers, propylene glycol, etc.). Specific examples of these estersinclude dibutyl adipate, di(2-ethylhexyl) sebacate, di-n-hexyl fumarate,dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctylphthalate, didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyldiester of linoleic acid dimer, the complex ester formed by reacting onemole of sebacic acid with two moles of tetraethylene glycol and twomoles of 2-ethylhexanoic acid, and the like.

Esters useful as synthetic oils also include those made from C₅ to C₁₂monocarboxylic acids and polyols and polyol ethers such as neopentylglycol, trimethylolpropane, pentaerythritol, dipentaerythritol,tripentaerythritol, etc.

Silicon-based oils such as the polyalkyl-, polyaryl-, polyalkoxy-, orpolyaryloxy-siloxane oils and silicate oils comprise another usefulclass of synthetic lubricants [e.g., tetraethyl silicate, tetraisopropylsilicate, tetra-(2-ethylhexyl) silicate, tetra-(4-methyl-2-ethylhexyl)silicate, tetra-(p-tert-butylphenyl) silicate,hexa-(4-methyl-2-pentoxy)-disiloxane, poly(methyl)-siloxanes,poly(methylphenyl)siloxanes, etc.]. Other synthetic lubricating oilsinclude liquid esters of phosphorus-containing acids (e.g., tricresylphosphate, trioctyl phosphate, diethyl ester of decylphosphonic acid,etc.), polymeric tetrahydrofurans and the like.

Unrefined, refined and rerefined oils (and mixtures of each with eachother) of the type disclosed hereinabove can be used in the lubricantcompositions of the present invention. Unrefined oils are those obtaineddirectly from a natural or synthetic source without further purificationtreatment. For example, a shale oil obtained directly from retortingoperations, a petroleum oil obtained directly from distillation or esteroil obtained directly from an esterification process and used withoutfurther treatment would be an unrefined oil. Refined oils are similar tothe unrefined oils except they have been further treated in one or morepurification steps to improve one or more properties. Many suchpurification techniques are known to those of skill in the art such assolvent extraction, acid or base extraction, filtration, percolation,etc. Rerefined oils are obtained by processes similar to those used toobtain refined oils applied to refined oils which have been already usedin service. Such rerefined oils are also known as reclaimed orreprocessed oils and often are additionally processed by techniquesdirected to removal of spent additives and oil breakdown products.

The phosphorus-containing compositions of this invention are also usefulas additives for metal working lubricants which are solid at roomtemperature. Such lubricants typically melt within the range from about30° to about 150° C., preferably from about 35° to about 70° C. They aresometimes referred to as "hot melt" lubricants since they are solid atroom temperature but melt at a temperature convenient for application inliquid form to the surface of the metal workpiece, solidifying againupon cooling to become dry, non-blocking and relatively non-slipperyunder storage conditions.

U.S. Pat. Nos. 4,116,872 and 4,191,658 are incorporated by referenceherein for their disclosures of ester-based metal working lubricants ofthe hot melt type in which the compositions of this invention can beadvantageously incorporated. The base lubricant in the ester-based hotmelt compositions, broadly defined, is at least one ester of acarboxylic acid. Typical esters are those of acids having the formula R⁵(COOH)_(m) and organic hydroxy compounds having the formula R⁶ (OH)_(n),wherein each of m and n is an integer from 1 to 3, R⁵ is ahydrocarbon-based radical, and R⁶ is a hydrocarbon-based orpoly(oxyalkylene) radical. The hydrocarbon-based radicals are usuallyfree from acetylenic and conjugated diene unsaturation and theypreferably contain no more than one olefinic double bond.

The acid typically contains from about 4 to about 25 carbon atoms. Thepreferred acids are the aliphatic carboxylic acids, especially those inwhich R⁵ is an alkyl or alkylene radical which may be branched orlinear. Exemplary acids are propionic, butyric, stearic, oleic, benzoic,maleic, fumaric, succinic, adipic, glutaric, pimelic, sebacic, azelaic,suberic, phthalic, isophthalic, citric and trimellitic acids. Theparticularly preferred acids are the aliphatic monocarboxylic acidshaving from about 12 to about 25 carbon atoms and polycarboxylic,especially dicarboxylic, acids having from about 5 to about 10 carbonatoms.

The organic hydroxy compounds in which R⁶ is a hydrocarbon-based radicaltypically contain at least about 10 and generally from about 10 to about25 carbon atoms. Usually, n is 1 and R⁶ is an alkyl radical which may bebranched or linear. Exemplary organic hydroxy compounds are 1-butanol,2-buten-1-ol, phenol, resorcinol, ethylene glycol, decanol, dodecanol,tetradecanol, stearyl alcohol, oleyl alcohol, eicosanol, and commercialmixtures of such alcohols. The preferred alcohols of this type aresaturated aliphatic alcohols containing at least about 10 carbon atoms,especially C₁₄₋₂₀ alkanols (that is, saturated monohydroxy alcohols) andmore especially predominantly straight-chain alkanols.

Another class of suitable organic hydroxy compounds consists of thepolyalkylene glycols, especially the polyethylene and polypropyleneglycols and preferably the former. The most desirable polyalkyleneglycols are those containing from about 20 to about 50 oxyalkyleneunits. Such polyalkylene glycols are normally available as commercialmixtures such as the "Carbowax" polyethylene glycols sold by UnionCarbide.

From the above descriptions of suitable acids and organic hydroxycompounds, it will be apparent that a wide variety of carboxylic acidesters are contemplated for use as hot melt lubricant bases. Theseinclude both neutral esters and acidic esters (e.g., monoesters ofdicarboxylic acids), but neutral esters are preferably used. Both mono-and bis-esters of polyhydroxy compounds are contemplated.

The preferred esters are of two types. Type A comprises neutral estersof saturated aliphatic alcohols having at least about 10 and preferablyup to about 25 carbon atoms and aliphatic polycarboxylic acids havingfrom about 4 to about 20 carbon atoms. Especially preferred within TypeA are esters of C₅₋₁₀ alkanedioic acids such as adipic, azelaic andsebacic acids and C₁₄₋₂₀ alkanols (particularly 1-alkanols) orcommercial mixtures of such alkanols.

Type B comprises esters of C₁₂₋₂₅ aliphatic monocarboxylic (preferablyalkanoic) acids such as myristic, palmitic and stearic acids, preferablystearic acid, and polyalkylene glycols (e.g., polyethylene orpolypropylene glycol, the former being preferred) containing from about20 to about 50 polyoxyalkylene units.

Mixtures consisting of about 5-95% by weight, and preferably about5-20%, of esters of Type A, the balance being esters of Type B, areparticularly desirable. Also useful are ester mixtures prepared byreacting a mixture of the above-described acids and alcohols.

Another genus of suitable hot melt lubricant bases comprises at leastone polymer of at least one monoepoxide or monoepisulfide, saidmonoepoxide or monoepisulfide having the formula ##STR1## wherein R⁷ isa substantially aliphatic hydrocarbon-based radical, each of R⁸, R⁹ andR¹⁰ is individually hydrogen or a substantially aliphatichydrocarbon-based radical, A is oxygen or sulfur, and the total numberof aliphatic carbon atoms in R⁷, R⁸, R⁹ and R¹⁰ is from about 6 to about23.

The term "substantially aliphatic" as used herein means that the radicalcomprises an aliphatic hydrocarbon-based chain which may, however,contain non-aliphatic substituents thereon. Such substituents includearomatic (e.g., phenyl and naphthyl), alicyclic (e.g., cyclohexyl andcyclopentyl) and heterocyclic (e.g., piperidyl and morpholino) groups.Such non-aliphatic groups will comprise no more than about 10% by weightof the substantially aliphatic hydrocarbon-based radical.

For the most part, R⁷ and each of the other R radicals (R⁸, R⁹ and R¹⁰)which are not hydrogen will comprise an aliphatic hydrocarbon radicaland usually an alkyl radical. Monoepoxides wherein the epoxy group is inthe α,β-position (those in which R⁹ and R¹⁰ are hydrogen) are preferredand those in which R⁸ is also hydrogen are especially preferred. Mostdesirable are epoxides of this type in which R⁷ is an alkyl radical(especially a straight chain one) containing from about 10 to about 18carbon atoms. Mixtures of such epoxides, including commerciallyavailable mixtures, are contemplated as suitable for the preparation ofpolymers for use in the invention.

Illustrative epoxides and episulfides whose polymers are useful as hotmelt lubricant bases are 1-octene oxide, 2-octene oxide,2,4,4-trimethyl-1-pentene oxide, 1-dodecene oxide, 1-hexadecene oxide,1-eicosene oxide, butyl epoxystearate, and commercial mixtures of C₁₂₋₁₈straight chain α-olefin epoxides. Polymers of the correspondingepisulfides are also useful.

The hot melt compositions of this type comprise at least one polymer ofan epoxide or episulfide as described above. Suitable polymers includehomopolymers of any single epoxide or episulfide and interpolymerscontaining units derived from more than one such epoxide, episulfide ormixture of epoxides with episulfides. They also include interpolymers ofan epoxide or episulfide as described above with a lower or highermolecular weight epoxide or episulfide, usually a lower alkyl one suchas ethylene oxide, propylene oxide or the corresponding sulfides. Ingeneral, such a copolymer containing units derived from epoxides orepisulfides other than those described above will contain a majoramount, usually above about 60% by weight, of units derived fromepoxides or episulfides having the above formula. The number averagemolecular weight of the polymer is generally between about 500 and10,000 as determined by gel permeation chromatography, and preferablybetween about 800 and about 2000.

The use of mixtures of two or more epoxide or episulfide polymers as ahot melt lubricant base is also contemplated. Specifically contemplatedare compositions comprising a mixture of (C) at least one polymer asdescribed hereinabove and (D) at least one polymer of ethylene oxide,propylene oxide or a mixture thereof. Such compositions will generallycontain at least 50% by weights, and preferably about 70-95%, ofcomponent C. Component D usually also has a number average molecularweight between about 500 and about 10,000, as determined by gelpermeation chromatography.

The epoxide or episulfide polymers are prepared by methods known in theart for the preparation of such polymers. A preferred method ofpreparation involves maintaining the epoxide or episulfide at atemperature up to about 60° C., preferably from about 30° to about 50°C., in the presence of a Lewis acid catalyst such as boron trifluorideor fluoboric acid. The following example is illustrative; all parts areby weight.

EXAMPLE 2

1-Hexadecene oxide (2000 parts) is cooled to 22° C. under nitrogen and29 parts of a 50% aqueous solution of fluoboric acid is added slowlyover 3 hours, with stirring. The reaction temperature is maintained at36°-43° C. by intermittent cooling. The temperature is maintained at40°-43° C. for one hour and is then increased to 50° C. as an additional5 parts of fluoboric acid solution is added. The catalyst is neutralizedby the addition of 11 parts of sodium carbonate and the product isfiltered through a filter aid material to yield the desired epoxidepolymer having a number average molecular weight of 1592 as determinedby gel permeation chromatography.

Particularly desirable extreme pressure properties are imparted to metalworking lubricants when the phosphorus-containing composition of thisinvention is incorporated therein in combination with a chlorinated wax,especially a chlorinated paraffin wax. The chlorinated wax preferablyhas a molecular weight between about 350 and about 700 and containsabout 30% to about 70% chlorine by weight, and the weight ratio ofphosphorus-containing composition to chlorinated wax is typicallybetween about 2.5:1 and about 0.5:1, preferably between about 1.5:1 andabout 1:1.

In general, the lubricating compositions may contain from about 5 toabout 30 parts by weight of the phosphorus-containing composition per100 parts of lubricant, with an amount of chlorinated wax adequate toprovide the weight ratios noted hereinabove. The lubricatingcompositions may additionally contain other additives. Especiallypreferred are carboxylic acids and derivatives thereof, which aretypically present in the amount of 1 part by weight for about every 1.2to 15 parts of phosphorus-containing composition. As used herein, theterm "derivative" includes:

Anhydrides.

Esters, especially those prepared from lower alkyl monohydroxy orpolyhydroxy compounds (e.g., methanol, ethanol, 1-butanol, n-hexanol,ethylene glycol, pentaerythritol) or epoxides (e.g., ethylene oxide,propylene oxide). The epoxide-derived compounds, as will be readilyunderstood, are hydroxy esters.

Salts (neutral, acidic or basic) in which the cation is preferably oneof a Group I or Group II metal, aluminum, tin, cobalt, lead, molybdenum,maganese, nickel or ammonium, including salts of the free acids and oftheir hydroxy esters. The lithium salts are preferred for theiranti-rust properties.

Amides and amide-imide mixtures, especially those derived from aliphaticamines and more especially from lower aliphatic amines. The preferredamines are the alkylene polyamines, particularly ethylene polyamines.

Derivatives of the type described above may be obtained from the acidsby known reactions or sequences of reactions.

The free acids, their lithium salts, and their anhydrides are mostuseful. Preferred are the aliphatic carboxylic acids (and derivativesthereof as defined hereinabove) containing from about 6 to about 75 andusually at least about 8 carbon atoms, and especially those in which thealiphatic radical is a hydrocarbon radical. These acids may bemonocarboxylic or polycarboxylic, and are preferably monocarboxylic ordicarboxylic. Examples of suitable monocarboxylic acids are decanoic,lauric, palmitic, stearic, oleic and linoleic acids, with oleic acidbeing preferred. The preferred dicarboxylic acids and derivatives arethe anhydrides of succinic acids having an aliphatic hydrocarbon-basedsubstituent, such as those prepared by the reaction (more fullydescribed hereinafter) of maleic acid or maleic anhydride with analiphatic hydrocarbon-based compound containing at least about 6 carbonatoms, preferably from about 6 to about 75 and most often from about 10to about 20 carbon atoms.

The hydrocarbon-based compound used for the preparation of thedicarboxylic acid or derivative thereof should be free from acetylenicunsaturation and substantially free from pendant groups containing morethan about six aliphatic carbon atoms.

The preferred hydrocarbon-based compounds are those derived fromsubstantially saturated petroleum fractions and olefin polymers,particularly oligomers of monoolefins (epsecially terinal monoolefins)having from 2 to about 10 carbon atoms. Thus, the hydrocarbon-basedcompound may be derived from a polymer of ethylene, propene, 1-butene,2-butene, isobutene, 3-pentene, 1-octene or the like. Also useful areinterpolymers of more than one olefin such as those illustrated above orof such olefins and other polymerizable olefinic substances such asstyrene, chloroprene, isoprene, p-methylstyrene, piperylene and thelike. In general, these interpolymers should contain at least about 80%,preferably at least about 96%, on a weight basis of units derived fromthe aliphatic monoolefins.

Other suitable hydrocarbon-based compounds are mixtures of saturatedaliphatic hydrocarbons such as highly refined high molecular weightwhite oils or synthetic alkanes.

In some instances, the hydrocarbon-based compound should contain anactivating polar radical to facilitate its reaction with the lowmolecular weight acid-producing compound. The preferred activatingradicals are halogen atoms, especially chlorine, but other suitableradicals include sulfide, disulfide, nitro, mercaptan, ketone andaldehyde groups.

As previously noted, the preferred method for producing the dicarboxylicacid or derivative thereof is by the reaction of maleic acid oranhydride with the hydrocarbon-based compound, especially with amaterial such as a propene oligomer. This reaction involves merelyheating the two reactants between about 100° and about 200° C. in thepresence or absence of a substantially inert organic liquid diluent; anexcess of a liquid reactant may also serve as the reaction medium. Othersuitable reactions include oxidation with potassium permanganate, nitricacid or a similar oxidizing agent of a hydrocarbon-substituted1,4-butanediol or the like; ozonolysis of a hydrocarbon-substituted1,5-diene or the like; preparation of a bisorganometallic derivative ofa hydrocarbon-substituted 1,2-dihalide or the like, followed bycarbonation thereof with carbon dioxide; or preparation of a dinitrilefollowed by its hydrolysis. All of these reactions are well known in theart, as are the substituted succinic acids and derivatives thereofproduced thereby.

Other additives which may be incorporated in the lubricants of thisinvention include:

Antioxidants, typically hindered phenols.

Surfactants, usually nonionic surfactants such as oxyalkylated phenolsand the like.

Auxiliary extreme pressure agents such as sulfurized hydrocarbons,sulfurized esters, phosphorodithioic acid salts, etc.

Corrosion and wear inhibiting agents, and auxiliary rust inhibitingagents.

Anti-stain agents such as salts of petrosulfonic acids, especiallyalkali metal salts and preferably sodium salts.

Friction modifying agents, of which the following are illustrative:C₁₀₋₂₀ fatty acid amides; C₁₀₋₂₀ alkyl amines, especially tallow amines,and ethoxylated derivatives thereof; salts of such amines with acidssuch as boric acid or phosphoric acid which have been partiallyesterified; C₁₀₋₂₀ alkyl-substituted imidazolines and similar nitrogenheterocycles; sulfurized derivatives of sperm oil and other fatty oils;basic barium or calcium salts of such oils or of amine-formaldehydecondensates, especially those derived from tallow amines such asdescribed above; and gels derived from basic alkaline earth metalsulfonates.

Thixotropic or non-drip agents. These may include waxes and mixtures ofaliphatic alcohols and hydrocarbons, especially those in about theC₂₀₋₃₄ range. Such alcohol-hydrocarbon mixtures are disclosed in U.S.Pat. No. 3,676,348, which is incorporated by reference herein for itsdisclosure thereof. The thixotropic agent need not be totally soluble inthe remainder of the lubricant at ambient temperatures. A preferredthixotropic agent is a commercially available solid mixture of linearand branched chain C₂₀₋₃₀ alcohols and C₂₄₋₄₀ hydrocarbons melting atabout 45°-50° C., sold by Ethyl Corporation under the trademark "Epal20+".

Waxes and waxy polymers may also be incorporated in hot melt metalworking lubricants. These include crystalline (includingmicrocrystalline) and non-crystalline hydrocarbon waxes, hydroxylatedhydrocarbon waxes, petrolatum, and low molecular weight olefin polymers.Such waxes or polymers are typically present in amounts between about0.25 and about 1.0 part by weight per part of lubricant base.

Small particle size, pigment-type particulate solids may also beincorporated in hot melt lubricants to increase lubricity attemperatures above the melting point thereof. Suitable in this respectare such pigments as rutile titanium dioxide, anatase titanium dioxide,zinc oxide, leaded zinc oxide, zinc sulfide, lead titanate, antimonyoxide, zirconium oxide, white lead, basic lead silicate, lithopone,titanated lithopone, titanium-barium pigment, titanium-calcium pigment,titanium-magnesium pigment, calcium carbonate, gilders whiting talc,barytes, magnesium silicate, aluminum silicates, diatomaceous earth,china clay, Asbestine, silica and mica. Calcium carbonate is especiallypreferred. The amount of such pigment is typically from about 0.1 toabout 0.2 part by weight per part of lubricant base.

It is preferred that the additives be soluble in the lubricant base, butthe invention also contemplates the use of a substantially stabledispersion of the additives in the lubricant base.

In the following table are listed illustrative metal working lubricants.Examples A and G are liquid lubricants, and Examples B-F are hot meltlubricants.

    __________________________________________________________________________                            Parts by weight                                                               Example                                               Ingredient              A  B C D E F G                                        __________________________________________________________________________    Mineral oil             16.1                                                                             --                                                                              --                                                                              --                                                                              --                                                                              --                                                                              16.1                                     Bright stock mineral oil                                                                              54 --                                                                              --                                                                              --                                                                              --                                                                              --                                                                              54                                       Neutral adipic acid ester of commerical mixture of                            predominantly straight-chain C.sub.16-18 l-alkanols*                                                  -- --                                                                              72                                                                              66                                                                              --                                                                              --                                                                              --                                       Stearic acid ester of "Carbowax 1540", a poly-                                ethylene glycol containing an average of                                      22-48 oxyethylene units per molecule                                                                  -- --                                                                              --                                                                              --                                                                              73                                                                              --                                                                              --                                       Ester mixture prepared from 0.75 equivalent of                                "Carbowax 1540", 0.25 equivalent of commercial                                mixture of predominantly straight-chain C.sub.14-18                           l-alkanols*, 0.75 equivalent of stearic acid                                  and 0.25 equivalent of adipic acid                                                                    -- --                                                                              --                                                                              --                                                                              --                                                                              80                                                                              --                                       Product of Example 2    -- 80                                                                              --                                                                              --                                                                              --                                                                              --                                                                              --                                       Product of Example 1    14 20                                                                              20                                                                              15                                                                              10                                                                              20                                                                              12.6                                     Chlorinated paraffin wax, mol. wt. about 560,                                 about 40% chlorine (by weight)                                                                        10 --                                                                              --                                                                              10                                                                               8                                                                              --                                                                              10                                       Sodium petroleum sulfonate                                                                            2.6                                                                              --                                                                              --                                                                              --                                                                              --                                                                              --                                                                              2.6                                      Tetrapropenyl succinic anhydride                                                                      -- --                                                                               8                                                                               9                                                                              --                                                                              --                                                                              --                                       Oleic acid              -- --                                                                              --                                                                              --                                                                              --                                                                              --                                                                              1.4                                      Dilithium salt of polybutenyl (mol. wt.                                       about 1000) succinic acid                                                                             3.3                                                                              --                                                                              --                                                                              --                                                                               9                                                                              --                                                                              --                                       __________________________________________________________________________     *Available from Procter & Gamble                                         

Any metal to be worked may be lubricated in accordance with thisinvention; examples are ferrous metals, aluminum, copper, magnesium,titanium, zinc and manganese as well as alloys thereof and alloyscontaining other elements such as silicon.

The lubricating compositions of this invention can be applied to themetal workpiece prior to or during the working operation in any suitablemanner. They may be applied to the entire surface of the metal, or withany portion of that surface with which contact is desired. For example,the lubricant can be brushed or sprayed on the metal, or the metal canbe immersed in a bath of the lubricant. In high speed metal formingoperations spraying or immersion are preferred.

In a typical embodiment of the invention, a ferrous metal workpiece iscoated with the lubricant prior to the working operation. for example,if the workpiece is to be drawn it may be coated with the lubricantbefore passage through the drawing die. It is also within the scope ofthe invention to apply the lubricant to the workpiece as it enters thedie, or to apply it to the die itself whereupon it is transferred to theworkpiece by contact. Thus, the method of this invention in a genericsense comprises any metal working operation wherein the workpiece has onits surface, during said operation, the above-described lubricantregardless of how applied.

The physical state of a hot melt metal working composition duringapplication to the metal surface is not critical. Thus, it may beapplied as a solid (as by rubbing) or as a liquid (as by brushing,spraying, dipping, flooding, roller coating, reverse roller coating orthe like). For ease and convenience of application, it is preferablyapplied in the liquid state, and when this is done the metal may besubsequently cooled whereupon the hot melt composition solidifies, or itmay be passed directly to the metal working operation while thecomposition is in the liquid state. One of the advantages of the hotmelt compositions, however, is that they solidify to form a solid,non-blocking, non-slippery film on the metal workpiece, thus permittingconvenient and safe material handling at reduced cost.

The surface temperature of the metal at the time the hot meltcomposition is applied may vary, for example, from normal ambienttemperature to just below the decomposition temperature thereof. Factorswhich will influence or determine the temperature of the metal at thetime the composition is applied include processes which the metal issubjected to prior or subsequent to application of the composition, themelting point of the composition, and the temperature thereof at thetime of application. Using the hot melt compositions describedhereinabove, metal surface temperatures between about 20° and about 125°C. at the time of application have been found particularly useful. Thetemperature of the hot melt composition should preferably be higher thanits melting temperature (preferably at least 10° C. higher and usuallyfrom about 20° to about 40° C. higher) at the time of application forease of flow and uniform dispersion of the composition onto the metaland coverage thereby.

The melted hot melt composition may be applied to the metal in a minimumof space utilizing existing equipment such as coilers used in steelmills prior to coiling, and because it quickly solidifies at ambienttemperatures and becomes dry, non-blocking and relatively non-slippery,standard handling equipment such as lifting and feeding rollers,stackers and so on may also be used. The use of the hot melt compositionalso eliminates the need for a dry-off oven since there is no water orsolvent to remove.

What is claimed is:
 1. A metal working lubricant comprising a majoramount of lubricating oil and a minor amount, effective to improve therust inhibiting and extreme pressure properties thereof, of aphosphorus-containing composition comprising at least one compoundhaving the formula

    (R.sup.1 --Ar.sup.1 OR.sup.2 O).sub.2 POH

wherein: Each R¹ is independently an aliphatic hydrocarbon-based radicalhaving from about 4 to about 100 carbon atoms; each R² is independentlyan ethylene, trimethylene, lower alkyl-substituted ethylene or loweralkyl-substituted trimethylene radical; and each Ar¹ is independently anaromatic radical.
 2. A lubricant according to claim 1 wherein R¹ is ahydrocarbon radical having from about 4 to about 25 carbon atoms, R² isethylene or propylene, and Ar¹ is a single-ring carbocyclic radical. 3.A lubricant according to claim 2 wherein Ar¹ is a phenylene radical. 4.A lubricant according to claim 3 wherein R² is ethylene.
 5. A lubricantaccording to claim 4 wherein R¹ is an octyl radical.
 6. A lubricantaccording to claim 1 which also includes at least one compound of theformula

    R.sup.3 --Ar.sup.2 OR.sup.4 Z

wherein: R³ is an aliphatic hydrocarbon-based radical having from about4 to about 100 carbon atoms; R⁴ is an ethylene, trimethylene, loweralkyl-substituted ethylene or lower alkyl-substituted trimethyleneradical; Ar² is an aromatic radical; and Z is chlorine or bromine.
 7. Alubricant according to claim 6 wherein R³ is identical with R¹, Ar² isidentical with Ar¹, R⁴ is identical with R², and Z is chlorine.
 8. Alubricant according to claim 7 wherein R¹ is a hydrocarbon radicalhaving from about 4 to about 25 carbon atoms, R² is ethylene orpropylene, and Ar¹ is a single-ring carbocyclic radical.
 9. A lubricantaccording to claim 8 wherein Ar¹ is a phenylene radical.
 10. A lubricantaccording to claim 9 wherein R² is ethylene.
 11. A lubricant accordingto claim 10 wherein R¹ is an octyl radical.
 12. A metal workinglubricant comprising a major amount of lubricating oil and a minoramount, effective to improve the rust inhibiting and extreme pressureproperties thereof, of a phosphorus-containing composition prepared byreacting at least one alcohol of the formula R¹ --Ar¹ OR² OH with atleast one phosphorus halide of the formula PZ₃, wherein:R¹ is analiphatic hydrocarbon-based radical having from about 4 to about 100carbon atoms; R² is an ethylene, trimethylene, lower alkyl-substitutedethylene or lower alkyl-substituted trimethylene radical; Ar¹ is anaromatic radical; and Z is chlorine or bromine.
 13. A lubricantaccording to claim 12 wherein R¹ is a hydrocarbon radical having fromabout 4 to about 25 carbon atoms, R² is ethylene or propylene, Ar¹ is asingle-ring carbocyclic radical, and Z is chlorine.
 14. A lubricantaccording to claim 13 wherein Ar¹ is a phenylene radical.
 15. Alubricant according to claim 14 wherein R² is ethylene.
 16. A lubricantaccording to claim 15 wherein R¹ is an octyl radical.
 17. A lubricantaccording to claim 1, 5, 6, 7, 11, 12 or 16 which additionally containsat least one carboxylic acid or derivative thereof.
 18. A lubricantaccording to claim 17 wherein the carboxylic acid is a monocarboxylic ordicarboxylic acid containing from about 6 to about 75 carbon atoms. 19.A lubricant according to claim 18 wherein the carboxylic acid is oleicacid.
 20. A method for lubricating metal during working thereof whichcomprises applying to said metal a lubricant according to claim 1, 5, 6,7, 11, 12 or
 16. 21. A method for lubricating metal during workingthereof which comprises applying to said metal a lubricant according toclaim
 17. 22. A method for lubricating metal during working thereofwhich comprises applying to said metal a lubricant according to claim18.
 23. A method for lubricating metal during working thereof whichcomprises applying to said metal a lubricant according to claim
 19. 24.A metal workpiece having on its surface a film of a lubricant accordingto claim 1, 5, 6, 7, 11, 12 or
 16. 25. A metal workpiece having on itssurface a film of a lubricant according to claim
 17. 26. A metalworkpiece having on its surface a film of a lubricant according to claim18.
 27. A metal workpiece having on its surface a film of a lubricantaccording to claim 19.